Obesity is associated with a wide variety of health problems, including Type 2 diabetes, hypertension, coronary artery disease, hypercholesteremia, sleep apnea, and pulmonary hypertension. It also exerts an enormous strain on the body that affects the organs, the nervous system, and the circulatory systems. Obesity rates have been rising for years in the United States, causing corresponding increases in healthcare expenditures.
Curing obesity has so far vexed the best efforts of medical science. Dieting is not an adequate long-term solution for most obese people, especially those with a body-mass index of over 30. Stomach stapling, or gastroplasty, reduces the size of the stomach, leading to reduced appetite and weight loss, but eventually the stomach stretches and the patient's appetite returns to pre-surgery levels. Roux-en-Y gastric bypass reduces the size of the stomach and the length of the intestine, and leads to both weight loss and alleviation of the Type 2 diabetes common to obese patients. Although gastric bypass appears to provide a more permanent solution than gastroplasty, complication rates associated with gastric bypass are between 2% and 6%, with mortality rates of about 0.5-1.5%.
Endoscopically delivered gastrointestinal implants, such as those described in commonly assigned U.S. Pat. Nos. 7,025,791 and 7,608,114 to Levine et al., incorporated herein by reference in their entireties, provide the benefits of gastric bypass without the hazards of surgery. For example, an implant may include a thin-walled, floppy sleeve that is secured in the stomach or intestine with a collapsible anchor. The sleeve extends into the intestine and channels partially digested food, or chyme, from the stomach through the intestine in a manner that may cause weight loss and improve diabetes symptoms. The sleeve and anchor can be removed endoscopically when treatment is over or if the patient desires.